Is there such a thing as a "soft" head?

[facarroll]

Just pulled the head off 200 Tdi and sent it away for skimming and crack testing. The response from the reconditioner was that there are no cracks, but because the motor got hot, the aluminium has become soft, and I should go for a reco head. Has anyone else ever heard of this, because it's new to me. He also says that I shouldn't use a composite gasket. I've already ordered an Elring from UK. Any useful advice. BTW, the gasket hadnt broken, but a straight edge showed warping. Leaking between numbers 2 and 3.

[isuzurover]

Just pulled the head off 200 Tdi and sent it away for skimming and crack testing. The response from the reconditioner was that there are no cracks, but because the motor got hot, the aluminium has become soft, and I should go for a reco head. Has anyone else ever heard of this, because it's new to me. He also says that I shouldn't use a composite gasket. I've already ordered an Elring from UK. Any useful advice. BTW, the gasket hadnt broken, but a straight edge showed warping. Leaking between numbers 2 and 3.

Very common on 300tdis - do a search.

[p38arover]

Yes.

They drop a small ball bearing onto the head. If the head is still hard, the ball will bounce quite well nad the head will ring.

If the head is soft, the ball doesn't bounce too well and the sound is more like a soft thud.

See http://www.engineworx.com.au/HardnessTesting.htm

and

http://www.jaeparts.com/gasket.pdf

[isuzutoo-eh]

You may also have luck searching for the term 'porous head'

[RobHay]

Soft heads are very common.........couple of fellows at work have them......err.......ahhhh........ engines...Yes....Soft heads on engines...Oh I see.......should read the post better. Similarly soft heads are a common result of cooking ya engine...and the metal swells particularly around the cylinder. The ball bearing in a tube is the best way to tell whether ya got a soft head.....I wonder how they would take to me bounceing ball bearings off their heads.

[isuzutoo-eh]

Soft heads are very common.........couple of fellows at work have them......I wonder how they would take to me bounceing ball bearings off their heads.

As long as the air pressure is high enough they might not complain at all :o

[d@rk51d3]

The ally heads can be re-hardened in many cases, although the cost is somewhat dearer than a new head................ if you can find one.

[Bigbjorn]

Common on Ford Falcon sixes. Ford not being big on quality components or quality control. When the cheap crap head gaskets Ford uses as OE fit leak, you generally find the head bolts are stuffed and often the head is too soft to reuse.

[rick130]

Bugger being a 200Tdi, heads are getting hard to find.

I believe you can have the head re-hardened if it isn't porous or cracked but unsure of costs involved and it may be hit and miss in the heat treatment department ?

I've also heard talk that a 300Tdi head may be able to be retrofitted, but unsure of the work involved as anything is doable, it all comes down to cost effectiveness.

BTW, Genuine and aftermarket parts are available from a couple of good suppliers in Sydney at wholesale prices ;)
Karcraft in Silverwater is who I deal with and I've heard good things of BMI at Mulgrave.

[facarroll]

I'll find out tomorrow about a reco head. Guess I'll store the buggered one for posterity. I went looking for a head, and found a brand new short motor assy for about $1500, but the freight was $1000. Don't need it but was tempted.

[blitz]

My missus reckons I'm soft in the head for owning a landrover is that the same thing???

[isuzurover]

Btw - it is not so much the overheating which softens/anneals the head, it is the rapid cooling.

Aluminium is opposite to steel. If you cool it down quickly it softens if you cool it down slowly it hardens. There are various other methods of hardening Al besides heat though.

There are a number of experienced heat treating companies in Melbourne. I would be inclined to look into the cost of getting your head re-hardened then machined.

[facarroll]

Where can I get this heat treatment?

[isuzurover]

Where can I get this heat treatment?

Just google "heat treatment Melbourne"

Here is one which specifically states they do Aluminium:
Heat Treatment Australia (http://www.heat.com.au/treatments.html)

John ( Bush65 ) is the metallurgy expert on here, however he doesn't seem to have been on here lately. He may be able to tell you the best company though.